1. If the current transformer is used in the relay protection circuit, it will start the misoperation or refusal of the relay protection layer device.
2. If the current transformer is used in the metering circuit of the instrument, the correct measurement of the power meter and the watt-hour meter will be affected.
3. The current transformers with incomplete star connection, if any polarity is reversed, it will cause the current of the unconnected current transformer to increase by more than that of other phases.
4. The current transformers with incomplete star connection are used. If the two phases are connected in reverse, although the three-phase current measured twice is still balanced, the phase angle difference with the corresponding primary current is 180°, which will cause electricity Table reversal. There are several wiring methods for current transformers. There are several different wiring methods for current transformers according to their application and different situations.
1. A current transformer is used for the wiring of the single-phase circuit. This wiring method is often used in three-phase symmetrical circuits to monitor the load current of one phase.
2. The two current transformers are connected in an incomplete star connection. This wiring method is suitable for measuring three-phase three-wire current, active and reactive power, and protecting short-circuit faults between phases.
3. Poor connection of two current transformers. This wiring method is suitable for protecting short-circuit faults between phases.
4. Three current transformers are connected in star connection. This connection method is used in a three-phase four-wire system to measure current, power and protect against short-circuit faults of any kind.
5. Use three current transformers to form a delta connection. This wiring method is used with three current relays to protect various short-circuit faults.
6. Three current transformers are used for zero sequence protection wiring. This wiring method is used for zero sequence protection.https://www.ctsensorducer.com/